The U.S. Supreme Court on Monday stopped same-sex marriage in its tracks in Utah, where state officials have been trying to block the practice after a federal judge effectively legalized it last month.

The high court granted a request from Utah for an emergency order to put gay marriage on hold while another court considers the state’s appeal, the Associated Press reports. That follows the Dec. 20 ruling from U.S. District Judge Robert Shelby, which struck down a voter-approved ban on same-sex marriage because he said it violated couples’ constitutional rights. Previous requests from the state for a stay had failed in lower courts.

More than 900 gay and lesbian couples have already married since the initial ruling. The status of those unions following the Supreme Court’s ruling is unclear. The Supreme Court stay will remain in effect until an appeals court rules on the matter.